*{
  margin: 0;
  padding: 0;
}
li{
  list-style: none;
}
a{
  text-decoration: none;
}
img{
  display: block;
}
em,i{
  font-style: normal;
}
html,body{
  width: 100%;
  height: 100%;
}
input{
  outline: none;
  padding-left: 5px;
}

/* banner start */
.bannerbg{
  width: 100%;
  height: 745px;
  background:url(../img/22.jpeg) no-repeat;
  background-size: cover;
  opacity: 0.2;
  position: absolute;
  z-index: -1;
  top: 0;
  left: 0;
  bottom: 0;
  right: 0;
  margin: auto;
}
.banner{
  width: 1170px;
  margin: 0 auto;
}
.banner .ban_con{
  width: 1170px;
  margin: 0 auto ;
  display: flex;
  justify-content: space-around;
}
.banner .ban_con>div img{
  margin-bottom: 20px;
  border: 2px solid rgba(137, 80, 0, 0.3);
  border-radius: 16px;
}
.banner .ban_con>div img:last-of-type{
  margin-bottom: 5px;
}
.banner .ban_con .high{
  margin: 20px 0 ;
}
.banner .ban_con .middle{
  margin: 60px 0 ;
}
.banner .ban_con .low{
  margin-top: 90px;
}
  


/* main start */
main{
  width: 1170px;
  /* height: 800px; */
  margin: 0 auto;
  /* border: 1px solid red; */
  
}
 main .science{
  margin-top: 50px;
  /* border: 1px solid red; */
}
main .science h2{
  font-size: 36px;
  color: #ff9a3b;
  margin-right: 30px;
}
main .science h2 span{
  font-size: 18px;
  font-weight: normal;
  margin-left: 10px;
  color: #a1a1a1;
}
main .science .sci_line{
  width: 300px;
  height: 2px;
  background-color: #ff9a3b;
}
main .science .sci_con{
  display: flex;
  justify-content: space-evenly;
  margin: 20px 0;
  flex-wrap: wrap;
}
main .science .sci_con .sci_line-left{
  width: 370px;
  margin-top: 20px;
  background: #fef7ef;
}
main .science .sci_con .sci_line-left h3{
  margin: 10px;
}
main .science .sci_con .sci_line-left h3 a{
  color: #ff9a3b; 
}
main .science .sci_con .sci_line-left h5{
  color: #af6117;
  font-size: 16px;
  font-weight: normal;
  margin: 10px;
}
main .science .sci_con .sci_line-left p{
  color: #a1a1a1;
  font-size: 14px;
  line-height: 1.5;
  margin: 10px;
}
.science .sci_line-left img{
  width: 100%;
  height: 260px;
}
